Lamp-grip.



` G. a; THOMAS.

LAMP GRIP. `Mmxcml'ow man 4Auezz. 1914.

Patented Feb. 20, 1917.

Eis womgws UNiTE sT Es ATENT o'EEiCE.;y

GEORGE B. THOMAS, OE BEIDGEPORT, CONNECTICUT, AssIG'NoE Tov THE BRYANT vELECTRIC COMPANY, OF BRIDGEPORT, CONNECTICUT,

NECTICUT.

To all whom t may concern.'

Be it known that I, GEORGE B. THOMAS, a citizen of 'the United States of America, and residing at Bridgeport, in the county vof Fairfield and State vof Connecticut, have invented a certain new and Improved Lamp-v Grip, of which the following is a specifica? invention relates to lamp; receptacles Fig. 3 is a perspective of the screw shell 1 contact of the socket; and

Fig. L is a perspective of a gripping device adapted to be used in the screw shell shown in Fig. 3.

While the present invention is applicable to lamp receptaclesjof all types inv which the lamp is adapted to be screwed into a socket of the Edison type, I have here shown it embodied ina pull socket having the usual casing comprising cap 10, shell 11, insulating lining 12 and bell mouth 13 through which the usual pull chain or cord is led from' the switch actiiating device within the socket.

Inasmuch as the switch mechanism forms no part 'of my invention, it is not shown. The center Contact 11i is mounted upon the usual insulating base 15 las is also `the screw shell side contact 16 into which the threaded base of the lamp 'is adapted to be screwed. Overlying the base flanges 17 of the screw shell I Ahave provided a reinforcing ring 18 held in position within the screw shell by 'means of the usual securing screws 19. From the margin of the ring 18 extend downwardlyv a plurality (here 3) spring fingers 20 which lie inside the thread 21 on the screw `shell and engage the entern ing base of the lamp. To permit these fingers to be spread by the entering lamp base, theside wall of the vscrew shell 16 is Specification of Letters Patent.

` cut away vupon the for gripping the and the pressure unshowing my invention here LAMEGEIP.

to Aafford slots 22 in lregister with the spring `ingers 20. Should the pressure to prevent the lamp from backing out, I provide inwardly struck prongs 23, Fig. 4, so formed that they. permit the 'lamp base to be readily screwed intothe socket shell,

butprovided Iwith engaging points 24 whichdig into the lamp basev on its reverse rota'- tion and thus prevent its accidental unscrewing.

. The operation of the'grip is obvious. 'As

lthe vlamp base is screwed into the socket shell 16, it engages the spring fingers -20 and tends to spread the latter. The spring fingers are free to yield through the 22 in the lam shell and consequently permit the lampI ase to be screwed home and into engagement with the center con-` tact 14, while at the saine time they add a suiiicient frictional grip upon the base to hold it against the backingy out. Where the prongs 23 are employed the is reinforced by their engagement with the lamp base. They do not however prevent the intentional removal upon the exertion of suicient force, the fingers 20 spread outward and the lamp base may be unscrewed. v

Various modifications embodying my in vention will readily suggestthemselves to those skilled in the art and I do not limit my invention to *the precise embodiment here shown and described.

A lamp 'receptacle comprising a screw slielll'side contact of theEdisontype, and an lying within independent lamp grip device said screw shell and having a'base'restingl In testimony whereof Il have signed my v name to this specification, in the presence of two subscribing witnesses.` f

CEORCEBTHOMAS.

Witnesses:

H. W. WICHERT, Gr. W. GooDRmCE.

slots frictional grip substan- A CORPORATION OE CON` Patented Feb. 20,1917. Application ineav August 25, 1914. serial No. $58,540.

lamp base be otherwise insufficient' of the lamp, since 

